Second Annual U.S. Future Circular Collider (FCC) Workshop 2024

25 Mar 2024, 07:30 → 27 Mar 2024, 17:30 America/New_York

Building 32, 32-123 (MIT)

Christoph Paus (staff@mit.edu)

design by Jordan Lang 

Overview

The annual US FCC workshop series started in 2023 at BNL with the idea of building and fostering the US community around the FCC and in particular the FCC-ee project. We will have the second instance of this workshop at MIT in Cambridge, MA.

After the long and rich Snowmass process and multiple P5 panel town hall meetings, the High-Energy Physics community has come to a conclusion on what to recommend to the DOE and NSF about our future. The P5 released its report including those recommendations on December 7/8, 2023. This workshop will allow the US FCC community to come together and discuss in detail the recommendations of P5. The DOE and NSF will be invited to this meeting, and we expect a fruitful discussion.

Status reports will be given on the FCC-ee accelerator, detector, computing & software and physics analysis program including theory. In addition, we will host a plenary session for the expression of interest of US institutions for potential contributions in the areas of: the accelerator, the emerging detector collaborations, the physics program, and the software/computing infrastructure development. Particular emphasis will be on young investigator and student contributions to the ongoing FCC-ee Feasibility Study.

The workshop dovetails nicely within the general FCC schedule, preceded by the FCC Physics days in Annecy (January 29 - February 2, 2024) and followed by the summer FCC Week in June.

International Organizing Committee

• Martin Aleksa (CERN)
• Patrizia Azzi (Padova)
• Anadi Canepa (FNAL)
• Sergei Chekanov (ANL)
• Sarah Eno (Maryland)
• Ayres Freitas (Pittsburgh)
• Julia Gonski (SLAC)
• Samuel Homiller (Harvard)
• Zoltan Ligeti (LBNL)
• Michelangelo Mangano (CERN)
• Christoph Paus (MIT)
• Marc-André Pleier (BNL)
• Srini Rajagopalan (BNL)
• Tor Raubenheimer (SLAC)
• Sally Seidel (New Mexico)
• Vladimir Shiltsev (NIU)
• Robert Szafron (BNL)
• Alessandro Tricoli (BNL)
• Christopher Tully (Princeton)

Local Organizing Committee

• Alisa Cabral
• Karen Dow
• Luca Lavezzo
• Elsye Luc
• Christoph Paus

Monday, 25 March

07:30 → 08:30 Registration

2nd-usfcc-workshop-mit.png

08:30 → 09:00 Opening Plenary: Welcome to the 2nd U.S. FCC Workshop at MIT!

08:30 Welcome to MIT

The head of the MIT Physics Department will welcome our guest at MIT.

Speaker: Deepto Chakrabarty (Massachusetts Institute of Technology)

08:45 Workshop Logistics

Speaker: Christoph Paus (MIT)

usfcc-welcome.pdf

usfcc-welcome.pptx

09:00 → 10:30 Plenary: Vision, P5 Report and FCC Status

Conveners: Alessandro Tricoli (BNL), Christoph Paus (staff@mit.edu), Sarah Eno (U. Maryland)

09:00 Particle Physics Questions and Opportunities at the FCC-ee

Speaker: Marcela Carena (FNAL)

Carena-FCC-MIT.pdf

09:30 Conclusions and Impact from the P5 Report

Speaker: Karsten Heeger (Yale)

P5-FCC-US-Heeger.pdf

10:00 Status of the FCC

Speaker: Michael Benedikt (CERN)

240325-FCC-FS-_Status.pptx

10:30 → 11:00 Coffee break

11:00 → 12:30 Plenary: Detector Concepts

Conveners: Marc-André Pleier (Brookhaven National Laboratory), Martin Aleksa (CERN)

usfcc-back-soon.pdf

11:00 The IDEA Concept

Speaker: Paolo Giacomelli (INFN Bologna)

IDEA_detector-concept-FCC-US-2024.key

IDEA_detector-concept-FCC-US-2024.pdf

IDEA_detector-concept-FCC-US-2024.pptx

11:30 [Remote] The CLD Concept

Speaker: Andre Sailer (CERN)

240325_sailer_cld.pdf

12:00 The ALLEGRO Concept

Speaker: Nicolas Morange (CERN)

allegro-concept.pdf

11:00 → 12:30 Theory Brainstorming about FCC

14:00 → 15:40 Plenary: Synergies in Machines, Detectors, Software and Theory

Conveners: Anadi Canepa (FNAL), Ayres Freitas (University of Pittsburgh)

usfcc-back-soon.pdf

14:00 Synergies: Physics and Performance

Speaker: Graham Wilson (University of Kansas)

MIT-Phys-Perf_GWW_V4.pdf

14:20 Synergies: Detectors

Speaker: Caterina Vernieri (Stanford)

MIT-workshop-Detector.pdf

14:50 Synergies: Software and Computing

Speaker: Lindsey Gray (FNAL)

SnCFCC_LindseyGray_26032024.pdf

15:10 Synergies: Accelerators

Speaker: Minty Michiko (BNL)

US-FCC Workshop MIT - Minty 25 Mar 2024.pdf

15:40 → 16:10 Coffee break and US FCC Workshop Photo

16:10 → 16:40 Plenary: Synergies in Machines, Detectors, Software and Theory: Part 2

usfcc-back-soon.pdf

16:10 Synergies: Theory Overview

Speaker: Matthew McCullough (CERN)

MIT.pdf

16:40 → 18:10 Plenary: Reports from DOE and NSF and Panel Discussion

Conveners: Sally Seidel (University of New Mexico), Srini Rajagopalan (BNL)

16:40 Introductory Remarks

Speaker: Srini Rajagopalan (BNL)

PanelDiscussionIntro.pdf

16:50 Panel Discussion with Haider Abidi (BNL), Tulika Bose (Wisconsin), Caterina Vernieri (Stanford), Robert Zwaska (FNAL), Chris Tully (Princeton), Michael Benedikt (CERN), Patrick Janot (CERN), Abid Patwa (DOE), Jim Shank (NSF)

Panel member include
Haider Abidi (BNL),
Tulika Bose (Wisconsin),
Caterina Vernieri (Stanford),
Robert Zwaska (FNAL),
Chris Tully (Princeton),
Michael Benedikt (CERN),
Patrick Janot (CERN),
Abid Patwa (DOE),
Jim Shank (NSF)

Speaker: TBD

18:30 → 20:30 Social events: Workshop Reception

18:30 Reception with Poster Session

In parallel to the reception we invite people to study the posters exhibited during the reception in the venue.

For more study they will be transported to the workshop foyer and will be available for day 2 and 3 of the workshop.

20:00 Measurement of Higgs decays to a bottom quark pair

We present a Monte Carlo analysis of a Higgs Boson decaying into two bottom quarks produced from electron-positron collisions at 240 GeV center-of-mass energy in the context of the Future Circular Collider (FCC) feasibility study. The Higgs boson decay to two bottom quarks is the most copious Higgs decay and its measurement will allow for the most precise determination of the Higgs couplings to fermions and in particular the b quark. We present an analysis that outlines the key steps including a first take at the leading uncertainties.

Speakers: Cailtlin Kubina (University of Maryland), Jacob Lee (University of Maryland), Joshua Robbins (University of Maryland), Sarah Waldych (University of Maryland)

20:05 Search for Higgs boson decaying to a Z boson and a photon

The FCC-ee would facilitate the search for the rare decay of $H \rightarrow Z + \gamma$ with greater precision. We present a feasibility study of the analysis in the Higgsstrahlung production channel, where the Higgs decays further into the Z and $\gamma$. The events are produced via Monte Carlo generators at a center-of-mass energy of 240 GeV and luminosity of 150 $ab^-1$ and the detector response is simulated at the IDEA detector. The decay channels are divided into four categories based on the final states of the two Z bosons ($4q$, $2q2l$, $4l$, and invisible). For each category, a selection method based on kinematic cuts and Boosted Decision Trees (BDTs) is employed to reduce the background processes, primarily the diboson (ZZ and WW) background. An uncertainty on the coupling constant $\kappa_{Z\gamma}$ is quoted for each category.

Speakers: Charlotte Myers (UMD), Peyton Musembi (UMD), Rujuta Sane (MIT), Yusuf Aamir (UMD)

20:10 Study of dimuon production a the Z pole

The Future Circular Collider (FCC) plans to measure the Z parameters at center-of-mass energies $$ \sqrt{s} \approx m_Z $$ via measurements of the dimuon cross section and forward-backward asymmetries. We produce a numerical model for the Z –> μ+μ- decay with a Monte Carlo simulation to make predictions. We replicate the measurements performed with the L3 detector in the years 1993–95 to verify our simulation and compare existing Monte Carlo generators, Whizard, KKMCee, and ReneSCANCe.

Speakers: Chinar Deshpande (MIT), Saina Deshpande (MIT), Satvik Manjigani (University of Maryland)

20:15 Comparison of Two Photon Monte Carlo generators at the FCC

We investigate qualitatively the relative performance of various Monte Carlo event generators (including Pythia8, and Whizard3) for generating the two-photon back ground in the leptonic and hadronic final states at the FCC-ee. We consider e+e− interactions at the Z pole, where the two-photon background is a non-negligible background for various electroweak precision analyses such as the muon and hadronic cross-sections. The two-photon background is of particular interest due to simulation difficulties of the γγ → hadron-hadron processes. We primarily study various kinematic variables for simulations of e+e− → γγ → e+e− + µµ interactions. We extend this analysis to e+e− → e+e− + hadrons interactions.

Speakers: Aneesh Anandanatarajan (University of Maryland), George Witt (University of Maryland), Othello Gomes (University of Maryland)

20:20 Tau lepton decay identification and polarization measurements at FCC-ee

The proposed FCC-ee collider will improve electroweak precision measurements by orders-of-magnitude, producing new measurements and potentially revealing inconsistencies within the Standard Model. In our work, we investigate tau polarization precision measurements in order to project finer uncertainties on fundamental SM parameters, including the weak mixing angle. We perform a realistic Monte Carlo study in the FCC-ee framework on the tau polarization at the center-of-mass energy of 91.2 GeV. Boosted decision trees (BDTs) are applied to optimize the identification of the 1-prong and 3-prong tau decay modes. These are then used to derive measurements of the tau polarization by fitting to analytical energy distributions.

Speakers: Isabella Vesely (MIT), Tim Neumann (student@mit.edu)

FCC Workshop Tau Lepton FCC-ee Study (Isabella and Tim)-2.pdf

Slides, with GIF Option

20:25 Measurement of W mass through kinematic analysis of its decay products

The W boson mass, an important parameter in the Standard Model, has a current measured value of 80.379 GeV with an uncertainty of 12 MeV. At FCC-ee, the expected precision should be reduced to below the 1 MeV level. A Monte-Carlo study is performed using the FCC-ee analysis framework through two decay channels of the W bosons (hadronic and semi-leptonic) at 180 GeV center-of-mass energy to determine the value of the W mass. The W boson mass and uncertainty are extracted from the decay products, the missing momentum and the kinematic constraints of the initial state.

Speakers: Jaime Ugedo (University of Maryland), Kristian Praizner (MIT), Nate Martinez (MIT), Noreldaim Ayman (MIT)

Tuesday, 26 March

08:30 → 10:00 Parallel: Accelerator and Machine Detector Interface (MDI)

Conveners: Tor Raubenheimer (SLAC), Vladimir Shiltsev (FNAL)

08:30 Research and Developments in the US towards the FCC RF/SRF systems

Speaker: Kellen McGee (FNAL)

US_FCC_SRF_activities_McGee.pdf

08:53 Research and Developments in the US towards the FCC IR magnets and MDI systems

Speakers: Kathleen Amm (BNL), Dr Maria Chamizo Llatas (BNL)

US contribution FCCeeMCL.pdf

US contribution FCCeeMCL.pptx

09:15 The FCC Accelerator Design/Dynamics Progress

Speaker: Vladimir Shiltsev (FNAL)

FCCeeDesignWork_Shiltsev_v1.pdf

09:30 [Remote] LCCO - New Beam Optics and Its Advantages

Speakers: Panataleo Raimondi (Fermilab), Pantaleo Raimondi

LCCO Boston Physics workwshop.pdf

LCCO Boston Physics workwshop.pptx

09:45 MDI

Speaker: Manuela Boscolo (INFN-LNF)

2400326__MDI_Mboscolo_MIT_US_FCC_workshop.pdf

08:30 → 10:25 Parallel: Computing and Software Tutorials

08:55 [Remote] From LHC to FCC-ee: Guiding I/O and data storage software of future multi-decade experiments with lessons learnt at ATLAS

Speaker: Alaettin Serhan Mete (Argonne National Laboratory (US))

20240326-METE.pdf

09:15 Delphes tutorial

Speaker: Jan Eysermans (Massachusetts Institute of Technology)

delphes_MG_Selvaggi.pdf

US_FCC_MIT_26032024.pdf

09:35 Tutorial on full simulations

Speaker: Brieuc Francois (CERN)

20240326_tutorial_fullSim_Brieuc_Francois_MIT.pdf

FCC-ee Full Sim Tutorial

10:05 Discussion time

10:00 → 10:30 Coffee break

10:30 → 12:32 Parallel: Detectors: Part 1

Conveners: Alessandro Tricoli (BNL), Sergei Chekanov (ANL)

10:30 Overview of Tracking and Timing Detector technologies for the FCC-ee detector

Speaker: Carl Haber (LBNL)

Technologies for Tracking and Timing.pdf

10:50 Design, performance and future prospects for a vertex detector for FCC

Speaker: Fabrizio Palla

MIT 2024.pdf

11:07 Development of precision tracking and quantum detectors at Fermilab

Speaker: Artur Apresyan (Fermilab)

Tracking and QIS at FNAL.pdf

11:24 MIT PixElPhi: a Pixel lab for ELementary Physics at MIT

Monolithic active pixel sensors (MAPS) represent the state-of-the-art technology for high-resolution, low-material budget detectors for particle-physics applications. The PixElPhi laboratory at MIT was recently created to exploit this technology for future nuclear and particle experiments. In this talk, we will present the activity and the plan for this laboratory, which currently focuses on the digital design, sensor characterization, and mechanical tests for the future Silicon Vertex Detector (SVT) of the ePIC experiment at the Electron-Ion Collider at the LHC. The future SVT detector will use bent and staved MAPS sensors in 65 nm CMOS imaging technology to build the most advanced MAPS-based detector so far developed. The MAPS-based detector technology developed in this lab for the SVT detector represents an ideal choice for the vertexing and tracking system of a future FCC experiment.

Speaker: Gian Michele Innocenti (Massachusetts Institute of Technology)

20240326_SVTInnocenti.pdf

11:39 Towards robust PICOSEC Micromegas precise timing detectors

Speaker: Sebastian White (University of Virginia)

fcc2MIT_SWHITE.pdf

11:56 High Segmentation, Radiation-Hard Calorimetry Options for FCC

Speakers: Yasar Onel (University of Iowa), Yasar Onel (University of Iowa)

Poster-SE.pdf

RadHardCal.pdf

USFCC2024_Onel_Calorimetry.pptx

12:13 Overview of TDAQ

Speaker: Zeynep Demiragli

Trigger and DAQ at FCC.pdf

10:30 → 12:30 Parallel: Theory and Experiment: Part 1

Conveners: Patrizia Azzi (Padova), Robert Szafron (BNL)

10:30 Beam-induced background simulation studies for FCC

A key aspect of evaluating the physics potential of any proposed Higgs factory is to quantify the effect of the various beam- and machine-induced backgrounds on the detector occupancy, and, ultimately, on the expected precision reach. In this work, we present results for the effects of incoherent pairs and photoproduced hadrons from beamstrahlung, which were interfaced with the SiD detector concept geometry, originally developed for the International Linear Collider (ILC), using the DD4HEP toolkit. Our studies demonstrate that FCC background rates are compatible with multiple detector concepts and enable further detector optimizations in order to maximize the precision of important measurements, e.g. the Higgs self-coupling. This highlights synergies between all Higgs Factory detector R&D efforts and shows the power of common software tools to enable physics studies for proposed future accelerators.

Speaker: Casey Lawson (MIT)

FCC_Beam_Studies_final.pdf

10:50 Opportunities and Challenges of the Hadron Cross Section at the Z pole

We present a study of the measurement of the cross section of hadronic Z decays at the Z pole. We will compare the state of the art Monte Carlo generators and we will compare the performance expected for the FCC-ee detectors with the LEP detectors. We also have a more detailed discussion of various backgrounds and their corresponding challenges.

Speaker: Marina Malta Nogueira (student@mit.edu)

Hadronic Cross-Section at the Z-pole.pdf

11:10 Alpha_s

Speaker: Iain Stewart (Massachusetts Institute of Technology)

Stewart_alphas.pdf

11:30 High Multiplciity e+e- collisions

This presentation focuses on the study of high multiplicity electron-positron (e+e-) collisions at the Future Circular Collider (FCC), particularly in the search for collective phenomena analogous to those observed in heavy ion collisions. Previous studies at the Z pole and LEP2 using archived ALEPH data have laid the groundwork for this exploration, but the FCC's capabilities offer a new frontier for investigating high particle density final states.

The talk will highlight how the FCC, with its significantly higher statistics, provides an unprecedented opportunity to study very high multiplicity events in e+e- collisions.

Speaker: Yen-Jie Lee (Massachusetts Institute of Technology)

20240326-FCC_yenjie_v6-post.pdf

20240326-FCC_yenjie_v6-post.pptx

11:55 [Remote] Study of the jet tagging performance using the ParticleNet tagger for the IDEA vertex detector

The ParticleNet tagger is a graph neural network devoted to the tagging of jets from the hadronization of multiple flavors. Its impressive and unprecedented tagging performance allows for accessing rare and challenging hadronic final states. This study shows the fast-simulation-based characterization of the ParticleNet performance evolution as a function of the IDEA vertex detector single-hit resolution, material radiation length and number of layers. Furthermore, an attempt to study impacts in physics applications such as the Z(qq)H and Z(inv)H final states will be shown.

Speaker: Andrea Sciandra

ASciandra_USFCCWS_26_03_24.pdf

12:15 From Optimal Observables to Machine Learning: an Effective-Field-Theory Analysis of $e^+e^- \to W^+W^-$ at Future Lepton Colliders

We apply machine-learning techniques to the effective-field-theory analysis of the
$e^+e^-\to W^+ W^-$ processes at future lepton colliders, and demonstrate their advantages in comparison with conventional methods, such as optimal observables. In particular, we show that machine-learning methods are more robust to detector effects and backgrounds, and could in principle produce unbiased results with sufficient Monte Carlo simulation samples that accurately describe experiments. This is crucial for the analyses at future lepton colliders given the outstanding precision of the $e^+e^-\to W^+ W^-$ measurement ($\sim \mathcal{O}(10^{-4})$ in terms of anomalous triple gauge couplings or even better) that can be reached. Our framework can be generalized to other effective-field-theory analyses, such as the one of $e^+e^-\to t\bar{t}$ or similar processes at muon colliders.

Speaker: Lingfeng Li (Brown University)

FCC_aTGC.pdf

13:30 → 15:29 Parallel: Detectors: Part 2

Conveners: Alessandro Tricoli (BNL), Sergei Chekanov (ANL)

13:30 Overview of Calorimeter technologies for the FCC-ee detector

Speaker: Nicolas Morange (Orsay, LAL)

nicolas-morange-calo.pdf

13:47 Dual-readout calorimetry with homogenous crystals and Precision timing characterization

Speaker: Grace Cummings (Fermi National Accelerator Laboratory)

GECummings_USFCCWorkshop_CalVision.pdf

14:04 Geant4 simulations of sampling and homogeneous hadronic calorimeters with dual readout for future colliders

Speaker: Sergei Chekanov (ANL)

FCCee_Geant4_dualreadout_March2024.pdf

14:21 Development of a segmented crystal ECAL option for IDEA.

Speaker: Wonyong Chung (Princeton University)

Chung_USFCC_March2024.pdf

14:38 Noble Liquid Endcap EM Calorimeter: Geometry and Simulation.

Speaker: John Rutherfoord (University of Arizona)

Turbine_Endcap_Ecal_USFCC_Mar_24.V3.pdf

14:55 Study of time and energy resolution of an ultracompact sampling calorimeter (RADiCAL) module at EM shower maximum over the energy range 25 ≤ E ≤ 150 GeV.

Speakers: James Wetzel (Coe College), Randy Ruchti (University of Notre Dame)

FCC_MIT_2024 Wide.pdf

15:12 Machine-learning for FCC simulations

Speaker: Raghav Kansal

FCC_Workshop_26_03_24.key.zip

FCC_Workshop_26_03_24.pdf

13:30 → 15:30 Parallel: Theory and Experiment: Part 2

Conveners: Patrizia Azzi (Padova), Robert Szafron (BNL)

13:30 Higgs physics and detector requirements

A major priority of the FCC-ee physics program is the measurement with the best possible precision the couplings of the Higgs Boson to other standard model particles. In this talk, we will present the current status of the physics potential for measuring these couplings. We will also discuss the latest developments in object identification tools essential for these measurements. Additionally, we will examine the impact of different detector performances on the overall measurement accuracy.

Speaker: Loukas Gouskos (Brown university)

lg_fccee_higgs_usfcc_2024mar.pdf

13:45 Prospects for Higgs to invisible at the FCC-ee

The precise measurement of the Higgs boson coupling to other standard model (SM) particles allows for up to 30\% of the Higgs boson width to originate from beyond the SM (BSM) decays. In the SM, the Higgs boson decays to invisible final states through the $H\rightarrow ZZ \rightarrow 4\nu$ process with a branching fraction of $(\mathcal{O})10^{-3}$ . This rate can be significantly enhanced if the Higgs boson decays into a pair of weakly interacting massive particles (WIMP), which may explain the nature of dark matter. The FCC-ee is a Higgs factory, with over one million Higgs bosons produced at $\sqrt{s} \sim$ 240 and 365 GeV, which can give access to Higgs decays with branching ratios of a fraction of a per mil. Preliminary studies of the invisible decay channel at FCC-ee are performed in the $Z\rightarrow H$ ($Z \rightarrow ff, H \rightarrow $ invisible) channel. We estimate the sensitivity at $\sqrt(s)=240$ GeV using full CLD simulation for the signal and smaller backgrounds. This is compared to earlier results using fast simulation. In addition, we propose to use the $H\rightarrow $ invisible channel to study the detector performance at the FCC-ee.

Speaker: Diallo Boye (Brookhaven National Laboratory)

Fcc-ee-mit-workshop.pdf

14:00 Higgs coupling in ZH di-jet and fully hadronic final states

The measurement of the Higgs boson properties at the future e+e− collider can be achieved through the Higgs-strahlung process. Analysis considering leptonic channels have been addressed but they might be statistically limited due to small branching ratios. This analysis extends the studies to full hadronic decays which represent a large branching ratios of about 70%. It also comes with great challenges since the jet clustering may create confusion and the assignment of jets to Higgs and Z comes with ambiguities. In this presentation ZH to full hadronic final state analysis using the state of the art jet tagger algorithm will be presented along with results for the precision that can be achieved. Moreover the combined fit results for the Z->inv. And the full hadronic will be shown.

Speaker: Iza Veliscek (BNL)

ZH All Had [FCC MIT Workshop]-2.pdf

14:15 Constraining CP-odd contributions in the Higgs-strahlung process at FCC-ee using kinematic observables

Prospects to constrain CP-odd contributions in the Higgs-strahlung process at a future electron-positron collider e+e- => ZH are presented. A realistic study is performed in the framework of the FCC-ee collider at the center-of-mass energy of 240 GeV, with reconstruction of the IDEA detector performed using the DELPHES framework. A matrix-element package, MELA, is implemented that uses event weights to the Standard Model in order to optimally constrain the CP-odd contributions based on kinematic observables.

Speaker: Nicholas Pinto (Johns Hopkins University)

MIT_FCC_Workshop_March26.pdf

MIT_FCC_Workshop_March26.pptx

14:30 Sensitivity to BSM fermions from Higgs precision studies

New fermions can be searched for directly at high-energy colliders, such as the LHC, or indirectly through precision measurements at e+e- colliders like FCC-ee. This talk presents the complementarity of these approaches for a broad class of simplified fermionic dark sectors models. The lightest new fermion could be stable or unstable. For the Higgs precision measurements we primarily focus on e+e- -> ZH, which is modified by the new fermions at the 1-loop level, and we also comment on the role of Higgs braching fractions and electroweak precision constraints.

Speaker: Ayres Freitas (University of Pittsburgh)

usfcc_freitas.pdf

14:45 Top Quark Couplings Prospects at Future Lepton Colliders

In this work we present the prospects for measurements of the top-quark couplings at future facilities, with special emphasis in lepton colliders. We will discuss projections for the high luminosity phase of the Large Hadron Collider and future Higgs/electroweak/top factory lepton colliders. Results are presented for the expected bounds on Wilson coefficients of the relevant SMEFT operators from a global fit to the top-quark physics sector.

Speaker: Fernando Cornet-Gomez (Case Western Reserve University)

Cornet_FCC_US_2024.pdf

15:00 ALPs at the FCC

Axion-like particles (ALPs) are pseudo Nambu-Goldstone bosons of spontaneously broken global symmetries in high-energy extensions of the Standard Model (SM). This makes them prime targets for future experiments aiming to discover new physics which addresses some of the open questions of the SM. While future high-precision experiments can discover ALPs with masses well below the GeV scale, heavier ALPs can be searched for at future high-energy lepton and hadron colliders. We discuss the reach of the different proposed colliders, focusing on resonant ALP production, ALP production in the decay of heavy SM resonances, and associate ALP production with photons, Z bosons or Higgs bosons. We discuss search strategies for ALPs decaying promptly as well as ALPs with delayed decays. Projections for the FCC-ee and FCC-hh will be presented.

Speaker: Andrea Thamm (University of Massachusetts Amherst)

Thamm_ALPs.pdf

15:30 → 16:00 Coffee break

16:00 → 17:30 Plenary: Lightning Talks

Conveners: Julia Gonski (Stanford), Samuel Homiller (Harvard)

16:00 ZH Jet Pairing Methods for Higgs Self-coupling Sensitivity Optimization at a Future Higgs Factory

In this talk, I will motivate the study of the ZH process as a means of studying Higgs self-coupling: measurements of Higgs self-coupling are essential as they are directly related to the shape of the Higgs potential, which has implications on the stability of the universe. This project analyzed various jet recombination schemes of a simulated ZH process, and aims to determine the jet reconstruction algorithm parameters that best identify the Higgs signal. This talk will provide an overview of the unexplored decay channel of ZH→cc bb and prove its value as a process of interest.

Speaker: Phillip Ionkov (BNL/Columbia University)

USFCC Presentation.pdf

16:10 Integrated CMOS Sensor Development for Future Colliders with a US-Based Foundry

This talk outlines an innovative program for the first-time development and production of High Energy Physics (HEP)-specific sensors, fully integrated into standard CMOS processes by a US-based foundry. Collaborating with US universities, our project focuses on designing and implementing Monolithic Active Pixel Sensors (MAPS) in 90 nm technology, encompassing test structures, multi-pixel arrays, and CMOS sensors with integrated readout circuits. I will discuss the design process, and prototype development of these detectors for HEP applications, highlighting the potential impact on future collider experiments.

Speaker: Chris Madrid (Fermilab)

Madrid_MAPS_Lightning.pdf

16:20 Electroweak Phase Transition and Higgs Exotic Decays

In this talk, I will inspire how the phenomenology of the Electroweak Phase Transition (EWPT) can guide the search for new physics related to the Higgs sector with the concrete example of Higgs exotic decays. EWPT is the transition from an electroweak symmetric phase to a broken phase in the early universe, and is a cross over in the Standard Model (SM). The EWPT being strongly first order is a necessary condition for electroweak baryogenesis, a mechanism that explains the baryon asymmetry of the universe. Thus, extending the Higgs sector to accommodate a strongly first order EWPT remains a motivated study for beyond the Standard Model physics. Importantly, the Higgs potential and properties are necessarily modified when new physics degrees of freedom are introduced to couple to the Higgs, leading to potential smoking-gun signals in Higgs searches. In the talk, I will present a concrete model example with a generic singlet extension to the Higgs sector, where there is a firm correlation between the prediction of a light scalar and a strongly first order EWPT. As the SM Higgs can decay into a pair of light scalars, the Higgs exotic decay is a unique channel to probe a broad class of EWPT models featuring light scalars.

Speaker: Yikun Wang (California Institute of Technology)

US FCC 2024.pdf

16:30 Dual-readout study with PbF2 crystals

We propose to use an electromagnetic calorimeter based on scintillating crystals to record both Cherenkov and scintillation light at the FCC-ee. Together with a dual-readout hadronic calorimeter, it will allow precise energy measurements of electrons, photons, and jets. In this talk, I'll report the first measurements that utilize PbF2 (non-scintillating crystals) to understand the collection of Cherenkov light, as a first step to study the dual-readout implementation of an electromagnetic calorimeter system.

Speaker: Yuxiang Guo (University of Michigan)

FCC_CalVision_MIT.pdf

16:40 A Simplified Model of Heavy Vector Singlets at the LHC and Future Colliders

I will introduce a simplified model for two colorless heavy vector resonances in the singlet representation of $SU(2)_L$, with zero and unit hypercharge, and use this model to motivate future collider efforts. I will discuss the semi-analytic production of these narrow resonances at proton colliders, and I will show current LHC constraints for a variety of two-body final states. In addition, I will draw on current limits to provide sensitivity projections for future high-energy colliders, discussing the role of the FCC-hh in future heavy resonance searches. The utility of this simplified model is illustrated by matching these results onto three explicit models: one weakly coupled abelian and one weakly coupled non-abelian extension of the Standard Model gauge group, and a strongly coupled minimal composite Higgs model. I will show that under these explicit models, the FCC-hh will constrain beyond the Standard Model vectors far above the reach of the LHC or similar future colliders.

Speaker: Timothy Martonhelyi (University of Massachusetts Amherst)

26_March_MIT_Vector_Singlets.pdf

16:50 Isosinglet vectorlike leptons at e+e- colliders

We study weak isosinglet vectorlike leptons that decay through a small mixing with the tau lepton, for which the discovery and exclusion reaches of the Large Hadron Collider and future proposed hadron colliders are limited. We show how an e+ e- collider may act as a discovery machine for these tau' particles, demonstrate that the tau' mass peak can be reconstructed in a variety of distinct signal regions, and explain how the tau' branching ratios may be measured.

Speaker: Prudhvi Bhattiprolu (University of Michigan)

pbhattiprolu.pdf

17:00 Long-lived Particles at the FCC-ee with the IDEA and CLD detectors

Long-lived particles are well motivated in numerous Beyond Standard Model theories including matter/antimatter asymmetry, the origin of electroweak symmetry breaking, Dark Matter, etc. The FCC-ee provides a unique opportunity to search for these distinct experimental signatures. We will present a study of the sensitivity of observing long-lived scalar particles originating from exotic Higgs boson decays at the FCC-ee. Furthermore, we will examine how the IDEA and CLD detector concepts affect the sensitivity to observing these long-lived particles.

Speaker: Mark Larson (Northeastern University)

Long Lived Particles at the FCC-ee with the IDEA and CLD detectors.pdf

17:10 What can we say about the Higgs self-coupling with the hadronic ZH process at FCC-ee?

A parameter of major interest in particle physics which has not yet been precisely measured is the Higgs self-coupling. A precise measurement of this coupling is fundamental to the Standard Model (SM), as it has a direct impact on the shape of the Higgs potential. A measurement consistent with the SM would further bolster the accuracy of the SM and confirm the expected meta-stability of the Higgs vacuum, while a measurement which disagrees could hint at the existence of new particles. While the Higgs self-coupling cannot be directly measured at FCC-ee due to a collision energy too low for HH production, it can be indirectly measured via single Higgs production. This talk will present projected constraints on the Higgs self-coupling using the fully-hadronic ZH process, taking advantage of the high ZH→hadrons branching ratio and the clean 𝑒+𝑒− collision environment.

Speaker: Abraham Tishelman-Charny (BNL)

26_March_2024_MIT_USFCC_WS_Selfcoupling.pdf

17:20 Overflow

19:00 → 21:00 Social events: Workshop dinner

Wednesday, 27 March

08:30 → 10:30 Plenary: Expression of Interest: Part 1

Conveners: Christoph Paus (staff@mit.edu), Julia Gonski (Stanford), Robert Szafron (BNL), Srini Rajagopalan (BNL)

EOI-FCC

EOI-FCC_as_shown.pptx

08:30 Southern Methodist University

Speaker: Ryszard Stroynowski

08:35 Florida Institute of Technology

Speaker: Marcus Hohlmann (Florida Institute of Technology)

08:40 Northern Illinois University

Speaker: Vladimir Shiltsev

08:45 Princeton

Speaker: Wonyong Chung

08:50 Northeastern

Speaker: Louise Skinnari

08:55 Johns Hopkins

Speaker: Andrei Gritsan

09:00 University of Virginia

Speaker: Bob Hirosky (U. Virginia)

09:05 Boston University

Speaker: Zeynep Demiragli

09:10 University of New Mexico

Speaker: Sally Seidel

09:15 University of Washington

Speaker: Shih-Chieh Hsu

09:20 Cornell (Accelerator Physics)

Speaker: Jared Maxson

09:25 Cornell (Physics)

Speaker: Anders Ryd

09:30 Michigan State

Speaker: Reinhard Schwienhorst

09:35 UMass Amherst

Speaker: Rafael Coelho Lopes de Sa

09:40 Texas Tech University

Speaker: Nural Akchurin

09:45 University of Iowa

Speaker: Yasar Onel

09:50 University of Pittsburgh

Speaker: Joseph Boudreau

09:55 Purdue University

Speaker: Andy Jung

10:00 Carnegie Mellon

Speaker: Valentina Dutta

10:05 University of Minnesota

Speaker: Roger Rusack

10:10 Brandeis

Speaker: Aram Apyan

10:15 Ohio State University

Speaker: K. K. Gan

10:20 Discussion/Overflow

10:30 → 11:00 Coffee break

11:00 → 13:00 Plenary: Expression of Interest: Part 2

Conveners: Christoph Paus (staff@mit.edu), Julia Gonski (Stanford), Robert Szafron (BNL), Srini Rajagopalan (BNL)

EOI-FCC

EOI-FCC_as_shown.pptx

11:00 Columbia

Speaker: John Parsons

11:05 MIT

Speaker: Christoph Paus (MIT)

11:10 University of Maryland

Speaker: Chris Palmer

11:15 University of Texas Austin

Speaker: Peter Onyisi

11:20 Tufts

Speaker: Hugo Beauchemin

11:25 UC Santa Cruz

Speaker: Jason Nielsen

11:30 University of Michigan

Speaker: Tom Schwarz

11:35 University of California Irvine

Speaker: Anyes Taffard

11:40 Stony Brook

Speaker: Valerio Dao

11:45 Caltech

Speaker: Ren-Yuan Zhu

11:50 University of Arizona

Speaker: John Rutherfoord

11:55 Duke

Speaker: Ashutosh Kotwal

12:00 Brown

Speaker: Loukas Gouskos

12:05 University of Kansas

Speaker: Graham Wilson

12:10 Argonne

Speaker: Alexander Paramonov

12:15 Brookhaven (Physics)

Speaker: Haider Abidi

12:20 Brookhaven (Accelerator Physics)

Speaker: Marc-André Pleier

12:25 Fermilab (Physics)

Speaker: Anadi Canepa

12:30 Fermilab (Accelerator Physics)

Speaker: Anadi Canepa

12:35 LBNL

Speaker: Carl Haber

12:40 Oak Ridge

Speaker: Mathieu Benoit

12:45 SLAC (Physics)

Speaker: Prajita Bhattarai

12:50 SLAC (Accelerator Physics)

Speaker: Spencer Gessner

12:55 Discussion/Overflow

14:00 → 15:40 Plenary: Closeout

Conveners: Alessandro Tricoli (BNL), Sarah Eno (Maryland)

14:00 Summary on Accelerators

Speaker: Vladimir Shiltsev

FCCeeAccelSummary_Shiltsev_v2.pdf

FCCeeAccelSummary_Shiltsev_v2.pptx

14:30 Summary on Detectors

Speaker: Felix Sefkow (DESY)

FCC-MIT-DetSum20240327.pdf

15:00 Summary on Theory and Measurements

Speaker: Hoeche Stefan (FNAL)

Theory_and_Measurements.pdf

15:30 Closeout

Speakers: Christoph Paus (MIT), Christophe Grojean (DESY, Humboldt University and CERN)

Grojean.pdf

usfcc-closeout.pdf

usfcc-closeout.pptx